Agronomy

It’s been largely ignored in the past as a route for phosphorus loss from farms, but the buried network of drainage pipes known as the tile system can carry away as much phosphorus as surface runoff.

That’s the conclusion of a pair of studies published in the Journal of Environmental Quality today (Oct. 3). In research in Ohio and Indiana led by USDA-ARS scientists, nearly 50% on average of both dissolved, “bioavailable” phosphorus and total phosphorus left fields via the tile system—a percentage much higher than previously thought.

The increasing scale of farming operations and use of agricultural machinery worldwide has caused an unusual problem—soil compaction. It’s defined as the packing effect of external forces that reduce soil bulk volume and pore size. Heavy farm equipment like tractors, trucks, and harvesters can cause soil compaction. Other causes include livestock and rainfall.

For decades, scientists, politicians and environmentalists have been trying to put a value on the Earth’s natural resources. Once public utilities were in place, homeowners had to start paying for the water provided by their municipalities. But, how much should that water service cost? In the late 1990s, it became common for people to buy bottled water. Pricing is largely determined by market forces.

Earthworms are a welcomed sight in many gardens and yards since they can improve soil structure and mixing. But they are hard to find in the drier soils of eastern Colorado where water and organic matter is limited. Adding earthworms to fields where they are not currently found could help enhance the health and productivity of the soil. In areas where droughts are common, though, can earthworms survive? A new study suggests that they can.

More than 600 million acres of grassland, pasture, and rangeland are found in the contiguous United States, much of which are fertilized with nitrogen to improve forage production. But as fertilizer costs and concerns over surface runoff from pastures and hay lands have risen, there has been renewed interest in nitrogen-fixing crops as an alternative to commercial fertilizers.